Grout discoloration often occurs due to a buildup of dirt, mold, mildew, or stains over time. The porous nature of grout makes it susceptible to absorbing liquids, leading to discoloration. To clean discolored grout, start by scrubbing it with a mixture of water and baking soda or a commercial grout cleaner using a stiff brush or an old toothbrush. For stubborn stains or mold, consider a mixture of equal parts vinegar and water. Apply the solution, let it sit for a few minutes, and scrub. Rinse with clean water and repeat as needed. Sealing grout after cleaning can also help prevent future discoloration and maintain its appearance.
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